In reply to John Williams's post on Wed 25 Nov 2015 (http://d-word.com/topics/129?post=332079):
Your issue is caused by a limited amount of memory on your iPad. You'll be more likely to experience this on an older model with a recent version of iOS. Basically those tablets don't have a lot of memory and newer iOS versions use tons of memory. I used to have the same experience on my iPhone 4s, but on a newer iPhone (which has more memory), Safari is now less likely to reload the page.
If it's possible to downgrade iOS to an earlier version (it may not be possible), that might help you.